AWS Strands Agents Team Releases Strands Harness: An Open-Source Agent Harness With 28% Lower Token Cost at Comparable Accuracy

An agent harness is the system around an AI model that handles the loop, tools, context management, memory, and recovery. AWS's Strands team released an open-source agent harness that achieves 28% lower token cost than comparable systems across six benchmarks while maintaining similar accuracy. The efficiency comes from three context management rules: truncating tool results over 1,500 tokens, triggering summarization when context usage passes 85%, and running context recovery if the window overflows. The harness can run locally or deploy to multiple cloud providers and works with various model providers through a single line of code.